Not until the end of the 19th century ______ become a scientific discipline. A. plant breeding has B. did plant breeding C. plant breeding had D. has plant breeding

SECTION II: LEXICO – GRAMMAR 

Part 1: Questions from 16 to 35. 

Choose the best answer from A, B, C or D to best complete the following sentences.

Not until the end of the 19th century ______ become a scientific discipline.